gistfile1.js

/*
 * jquery dialog - display the "OK" button in a disabled state
 * removes the function from the button and adds the class "ui-state-disabled" 
 */
    if(data.length>0){
        options="";
        $.each(data, function(i, product){
          if(product.product.id!=product_id){
          options+= '<option value="'+product.product.id+'">'+product.product.name+'</option>';
          }else{
          options+= '<option value="'+product.product.id+'" selected="selected">'+product.product.name+'</option>';
          }
        });
        $('#product_id').append(options);

        $('#product_selection_dialog').dialog('option', 'buttons', { 
          "OK": function() {
            selectedElement=$('#product_id :selected').text();
            $("#product_name_"+$('#product_selection_dialog').attr("row_id")).text(selectedElement);
            var id='#list_list_items_attributes_';
            $(id+$('#product_selection_dialog').attr("row_id")+'_product_id').attr('value',$('#product_id').val());
            $('#product_selection_dialog_button_'+$('#product_selection_dialog').attr("row_id")).attr('category_id',$('#product_category_id').val());
            $(this).dialog("close"); 
          },
          Cancel: function() {
            $(this).dialog("close"); 
          }
          }
        );
      }else{
        $('#product_selection_dialog').dialog('option', 'buttons', { 
          Ok: function() { }
          ,
          Cancel: function() {
            $(this).dialog("close"); 
          }
        });
        var okb=$('.ui-dialog-buttonpane button:last').prev();
        okb.addClass('ui-state-disabled');
      }